Known as “Blackbird”, the SR-71 was a US Air Force (USAF) long-range strategic
reconnaissance aircraft that served between 1964 and 1998. Operating at high
altitude (24,000m) and cruising at speeds of Mach 3.2, it could simply outrun
surface-to-air missiles! The SR-71 was developed as a black project by the Lockheed
Skunk Works. A total of 32 aircraft were built, and as testament to its effectiveness,
none were ever lost in combat despite being fired on 4,000 times. However, twelve
Blackbirds were lost to accidents. Much of the airframe is made of titanium
in order to address the issue of high temperatures created by supersonic speeds.
The panels were designed for thermal expansion, meaning on the ground they only
fitted loosely, before reaching proper alignment in flight. The SR-71 holds
the record for the fastest air-breathing manned aircraft when it attained a
speed of 3529km/h, propelled by its Pratt & Whitney J58-P4 engines. The
SR-71 was used extensively in combat in the skies over Vietnam and Laos, and
throughout the course of its career this revolutionary aircraft completed 17,300
sorties.